This invention relates to a device for limiting the collapse of a vehicle structure on frontal impact, and in particular for limiting the movement of the body sides away from each other while at the same time also limiting the rearward movement of the steering column into the vehicle passenger compartment. Currently, vehicle body sides are connected together at their front by a cross-member of box structure, the opposing ends of which are welded or bolted directly to the body sides and/or to support brackets rigidly provided on the inner surfaces of the body sides. Such a structure has the drawback of being relatively weak if the vehicle suffers frontal impact. In such a case, the stresses produced by the impact result in simultaneous tensile and torsion/shear stressing of the cross-member. In particular, the torsion and shear stresses are a maximum precisely at the points at which the cross-member is connected to the body sides, and this, in the case of particularly violent impact, can produce the partial or indeed total separation of the cross-member from the body sides by fracture of the weld spots and/or of the other connection means used, and also because generally the cross-member is fixed to the body sides by a relatively small number of weld spots and/or bolts, especially if little space is available thus making the joining operations difficult and limiting the reliability and quality of the welds made.
It is also known, for example from German patent application No. 3627558, to limit the rearward movement of the steering column on frontal impact by connecting the steering column by a cable to the engine-gearbox unit so that the rearward movement of the engine-gearbox unit on impact produces a forward pull on the steering column. However, such an arrangement is not always useful in the case of impact, particularly if the dynamics of the impact are such as to produce only a limited (or zero) movement of the engine-gearbox unit, but at the same time a much greater movement of the steering column.